U.S. patent application number 15/484597 was filed with the patent office on 2017-10-12 for conductive self-healing network.
The applicant listed for this patent is Board of Regents, The University of Texas System. Invention is credited to Xiaopeng Li, Ye Shi, Guihua Yu.
Application Number | 20170292008 15/484597 |
Document ID | / |
Family ID | 59999230 |
Filed Date | 2017-10-12 |
United States Patent
Application |
20170292008 |
Kind Code |
A1 |
Yu; Guihua ; et al. |
October 12, 2017 |
CONDUCTIVE SELF-HEALING NETWORK
Abstract
Disclosed herein are self-healing conductive network
compositions. The networks can contain one or more conductive
polymers and one or more supramolecular complexes. The
supramolecular complex can be introduced into conductive polymer
matrix, resulting in a network of the two components. In this
network, the nanostructured conductive polymer gel constructs a 3D
network to promote the transport of electrons and mechanically
reinforce the network while the supramolecular complex contributes
to self-healing property and also conductivity. The networks
disclosed herein are useful for various applications such as
self-healing electronics, artificial skins, soft robotics and
biomimetic prostheses.
Inventors: |
Yu; Guihua; (Austin, TX)
; Shi; Ye; (Austin, TX) ; Li; Xiaopeng;
(Austin, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Board of Regents, The University of Texas System |
Austin |
TX |
US |
|
|
Family ID: |
59999230 |
Appl. No.: |
15/484597 |
Filed: |
April 11, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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62320909 |
Apr 11, 2016 |
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62320969 |
Apr 11, 2016 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08G 61/124 20130101;
C08K 5/3432 20130101; C08K 5/5442 20130101; C08G 2261/51 20130101;
C08G 2261/37 20130101; C08G 2261/3221 20130101; C08G 2261/50
20130101; C08G 2261/792 20130101; H01B 1/127 20130101; C08G 2210/00
20130101; C08G 2270/00 20130101; C08G 2261/11 20130101; C08G
2261/62 20130101; C08L 65/00 20130101; C08L 101/14 20130101; C08L
65/00 20130101; C08L 87/00 20130101 |
International
Class: |
C08K 5/3432 20060101
C08K005/3432; H01B 1/12 20060101 H01B001/12; C08G 61/12 20060101
C08G061/12 |
Claims
1. A self-healing, conductive network comprising: a conductive
polymer; and a supramolecular complex.
2. The network according to claim 1, in the state of a gel.
3. The network according to claim 2, further comprising a
solvent.
4. The network of according to claim 1, wherein the ratio (w/w) of
conductive polymer and supramolecular complex is from about 25:1 to
1:25.
5. The network of according to claim 1, wherein the conductive
polymer comprises a polyaniline, a polypyrrole, a polythiophene, a
polystyrene sulfonic acid, or a combination thereof.
6. The network according to claim 1, wherein the conductive polymer
comprises a compound of the formula: ##STR00019## wherein R is
C.sub.1-6 alkyl, C.sub.1-6 alkoxy, C.sub.1-6 haloalkyl, C.sub.1-6
haloalkoxy, F, Cl, Br, I, CN, NO.sub.2, n is 0, 1, 2, 3 or 4, m is
0, 1 or 2, X is NH, O, S, Se, or a mixture thereof.
7. The network according to claim 1, wherein the conductive polymer
comprises a dopant.
8. The network according to claim 1, wherein the conductive polymer
comprises a dopant comprising a polybasic compound.
9. The network of claim 1, wherein the supramolecular complex is
characterized by a sol-gel transition temperature no greater than
about 75.degree. C.
10. The network according to claim 1, wherein the supramolecular
complex comprises an organometallic complex having cubic
architecture.
11. The network according to claim 1, wherein the supramolecular
complex is represented by the formula M.sub.12L.sub.8, wherein M
represents a transition metal and L represents a tritopic
ligand.
12. The network according to claim 11, wherein M is selected from
the group consisting of Zn, Cd, Ni, Co, Fe, Ru, Mn and combinations
thereof.
13. The network according to any of claim 11, wherein the
supramolecular complex comprises a tritopic ligand having the
formula: ##STR00020## wherein: Z is a group of the formula:
##STR00021## wherein each represents a bond to a B.sup.3.sub.yyy
group, .PHI. represents a 1,4 phenylene, z is either 0 or 1, and
R.sup.z is selected from hydrogen, C.sub.1-12 alkyl, C.sub.3-12
cycloalkyl, C.sub.1-12 alkoxy, C.sub.2-12 heterocyclyl, C.sub.6-12
aryl, C.sub.3-12 heteroaryl, poly(alkylene glycol), crown ethers,
and pillarene; x, xx, and xxx are each independently 0 or 1, and
A.sup.1, A.sup.2 and A.sup.3 are independently selected from:
##STR00022## y, yy, and yyy are each independently 0, 1 or 2, and
B.sup.1, B.sup.2 and B.sup.3 are independently selected from
##STR00023## wherein R is in each case independently selected from
hydrogen, F, Cl, Br, I, OH, COOH, NO.sub.2, C.sub.1-6 alkyl,
C.sub.1-6 haloalkyl, C.sub.3-6 cycloalkyl, C.sub.1-6 alkoxy,
C.sub.2-12 heterocyclyl, C.sub.6-12 aryl, and C.sub.3-12
heteroaryl, and wherein any two or more R groups may together form
a ring; with the proviso that the sum of x, xx, xxx, y, yy, and yyy
is not 0; R.sup.b and R.sup.d are independently selected hydrogen,
halogen (e.g., F, Cl, Br, I), OH, COOH, NO.sub.2, C.sub.1-6 alkyl,
C.sub.1-6 haloalkyl, C.sub.3-6 cycloalkyl, C.sub.1-6 alkoxy,
C.sub.2-12 heterocyclyl, C.sub.6-12 aryl, and C.sub.3-12
heteroaryl; R.sup.a and R.sup.c are independently selected from:
##STR00024## or wherein either R.sup.a and R.sup.b or R.sup.c and
R.sup.d, together form a group having the structure: ##STR00025##
wherein R.sup.1 is in each case independently selected from
hydrogen, halogen, C.sub.1-C.sub.6 alkyl, C.sub.1-C.sub.6 alkoxy,
and C.sub.1-C.sub.6 haloalkyl, R.sup.2 is in each case
independently selected from C.sub.1-C.sub.6 alkyl, and wherein any
two or more of R.sup.1 or R.sup.2 may together form a ring.
14. The network according to claim 13, wherein Z has the formula:
##STR00026##
15. The network according to claim 13, wherein R.sup.b and R.sup.d
are both hydrogen, and R.sup.a and R.sup.c each have the formula:
##STR00027##
16. The network according to claim 15, wherein R.sup.1 is in each
case tert-butyl.
17. A method of making the self-healing, conductive network of
claim 1, comprising the step of combining a dry conductive polymer,
supramolecular complex, and a solvent, and partially evaporating
the mixture to give a self-healing, conductive network.
18. The method of claim 17, wherein the solvent comprises water,
acetonitrile, THF, DMF, DMSO, or a mixture thereof.
19. The method of claim 17, wherein the network, after partial
evaporation, comprises from about 40-60% by weight of the
solvent.
20. The method of claim 17, wherein the ratio of dry conductive
polymer to supramolecular complex is from 20:1 to 1:1.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional
Applications 62/320,909, filed Apr. 11, 2016, and 62/320,969, filed
Apr. 11, 2016, the contents of each are hereby incorporated in
their entirety.
FIELD OF THE INVENTION
[0002] This invention is directed to conductive gels with
self-healing properties.
BACKGROUND
[0003] Self-healing materials with conductive properties have
attracted growing interest in both academia and industry due to
their potential applications in a broad range of technologies, such
as self-healing electronics, medical devices, artificial skins, and
soft robotics. For practical applications, these materials should
demonstrate good conductivity and repeatable mechanical and
electrical self-healing properties at room temperature, as well as
decent mechanical strength and flexibility, to meet the
requirements for fabrication of flexible devices.
[0004] Great efforts have been dedicated to developing conductive
self-healing materials. Researchers have developed the use of
microcapsules containing liquid precursor healing agents for
structural healing. In these systems, the local healing agent is
depleted after capsule rupture. Others have demonstrated an
alternative approach by combining a supramolecular organic polymer
and nickel microparticles, resulting in a composite with mechanical
and electrical self-healing properties at ambient conditions;
whereas a large number of inorganic particles are needed for the
preparation of composite. Recently, a conductive and self-healing
hydrogel has been synthesized by polymerization of pyrrole within
agarose matrix. The self-healing behavior of the resultant
composite, however, can only be excited under external thermal or
optical stimuli. Therefore, the development of self-healing, highly
conductive, mechanically strong, and light-weight materials remains
a critical challenge.
[0005] In the past decades, the supramolecular chemistry has
witnessed rapid development of metallo-supramolecular structures
based on the highly directional and predictable feature of
metal-mediated self-assembly. Driven by directional and conjugated
structures and intermolecular forces, these supramolecular
structures could further hierarchically self-assemble into higher
order nanostructures, i.e., supramolecular gels. More importantly,
due to the moderate bond energy of metal-ligand bonds and
non-covalent interactions among supramolecules, the supramolecular
gels can dynamically assemble or disassemble, associate or
dissociate at room temperature, thus showing features such as
self-healing property and sol-gel phase transitions. Recently,
conductive polymer hydrogels (CPHs) such as polyaniline (PANI) and
polypyrrole (PPy) hydrogels have been synthesized using phytic acid
as the gelator and dopant. The framework of the resulted CPHs
provides ideal 3D interconnected paths for electron transport, thus
reaching a conductivity as high as 11 S/m. Such 3D hierarchically
porous structures offer large open channels to support the
introduction of second gel component and provide an ideal interface
between conductive hydrogels and other synthetic systems. However,
the fragile nature and lack of self-healing property inhibits CPHs'
further applications.
[0006] There is a need for conductive materials exhibiting
self-healing behavior. There is a need for materials with good
conductivity, repeatable mechanical and electrical self-healing
properties at room temperature, and good mechanical strength and
flexibility. There is a further need for a method providing a
variety of networks using a common synthetic strategy.
[0007] The invention disclosed herein addresses, in part, one or
more of the aforementioned needs.
SUMMARY
[0008] Disclosed herein are self-healing conductive network
compositions and methods of making the same. The networks can
contain one or more conductive polymers and one or more
supramolecular complexes. The supramolecular complex can be
introduced into conductive polymer matrix, resulting in a network
of the two components. In this network, the nanostructured
conductive polymer gel constructs a 3D network to promote the
transport of electrons and mechanically reinforce the network while
the supramolecular complex contributes to self-healing property and
also conductivity. The networks disclosed herein are useful for
various applications such as self-healing electronics, artificial
skins, soft robotics and biomimetic prostheses.
[0009] Conductive polymers useful in the disclosed networks include
polyanilines, polypyrroles, polythiophenes, and combinations
thereof. The conductive polymer can include at least one polyacid
dopant.
[0010] The supramolecular complex can be an organometallic complex,
and in certain embodiments can have a cubic architecture. The
supramolecular complex can be formulated as a gel which, when apart
from the conductive polymer, can be characterized by a sol-gel
transition of less than or about 80.degree. C., less than or about
70.degree. C., less than or about 60.degree. C., or less than or
about 50.degree. C. The low sol-gel transition temperature allows
supramolecular complex fragments to reassemble near a damaged area
of the network, thereby permitting self-healing.
[0011] Cubic supramolecular organometallic complexes can include
tritopic ligands, held together by ditopic metal-ligand bonds.
Cubic supramolecular organometallic complexes can have the formula
M.sub.12L.sub.8, in which M is a metal and L is a tritopic ligand.
Tritopic ligands can have a central core, from which three rigid
spacer moieties extend, said spacers terminated with a chelating
group. In some instances, the chelating group can be a tridentate
chelating group.
[0012] Self-healing conductive networks can be obtained from a
conductive hydrogel and a supramolecular complex. The hydrogel can
be dehydrated to form an aerogel, which can be mixed with the
supramolecular complex in a suitable solvent to give the
self-healing conductive network.
[0013] The details of one or more embodiments are set forth in the
descriptions below. Other features, objects, and advantages will be
apparent from the description and from the claims.
BRIEF DESCRIPTION OF THE FIGURES
[0014] FIG. 1A includes a depiction of a cubic supramolecular
complex having the Formula M.sub.12L.sub.8.
[0015] FIG. 1B includes a depiction of the sol-gel transition of a
G-Zn-tpy/MeCN composition. The concentration of G-Zn-tpy to MeCN is
approximately 5-10 wt %.
[0016] FIG. 2A includes a depiction of the storage modulus (G') of
a supramolecular complex gel (triangles), a conductive hydrogel
(circles) and network containing a conductive polymer and
supramolecular complex (squares).
[0017] FIG. 2B includes a depiction of the loss modulus (G'') of a
supramolecular complex gel (triangles), a conductive hydrogel
(circles) and network containing a conductive polymer and
supramolecular complex (squares).
[0018] FIG. 2C includes a depiction of the tangent of the phase
angle (G''/G') of a supramolecular complex gel (triangles), a
conductive hydrogel (circles) and network containing a conductive
polymer and supramolecular complex (squares).
[0019] FIG. 3A includes a picture of a network thin film coated on
a Kapton substrate.
[0020] FIG. 3B includes a depiction of the film resistance of a
network thin film coated on PDMS substrate under different
stretching states. Inset (left) shows the film resistance after
different stretching cycles and inset (right) shows the optical
images of network thin film at initial status and 67% strain.
[0021] FIG. 3C includes a depiction of the conductivy of a network
thin film under different bending states. Inset shows the optical
images of bended network thin film coated on PDMS substrate.
[0022] FIG. 3D includes a depiction of the conductivities of a
network thin film after different bending cycles. Inset shows
optical images of bended network thin film coated on Kapton
substrate.
[0023] FIG. 3E includes a depiction of a compression test for an
unstretched network thin film (solid line), a network thin film
having undergone a self-healing process (long dashes), a conductive
hydrogel (dots), and a cut network (dots and dashes).
[0024] FIG. 3F includes a depiction of the conductivities of a
network at different stages during cutting and self-healing
processes. The cut samples were physically contacted to each other
to initiate self-healing.
[0025] FIG. 4A-4D includes a depiction of the self-healing property
of a network: A bulk sample was cut into half and then placed
together. After 1 min, the two samples self-healed into an
integrated film, which could support its own weight when lifted by
a tweezers;
[0026] FIG. 5 includes a depiction of a self-healing circuit based
on a network: (5-1) and (5-2) include optical images of circuit
based on a network film at open and closed states; (5-3) and (5-4)
demonstrate that the circuit functions well under bended and folded
states; (5-5) and (5-6) include a depiction of the self-healing
behavior of designed circuit: the left side of network film was cut
and the circuit became open and the bulb was extinguished. After 1
min of self-healing, the circuit was re-established and the LED
bulb could be lighted again.
DETAILED DESCRIPTION
[0027] Before the present methods and systems are disclosed and
described, it is to be understood that the methods and systems are
not limited to specific synthetic methods, specific components, or
to particular compositions. It is also to be understood that the
terminology used herein is for the purpose of describing particular
embodiments only and is not intended to be limiting.
[0028] As used in the specification and the appended claims, the
singular forms "a," "an" and "the" include plural referents unless
the context clearly dictates otherwise. Ranges may be expressed
herein as from "about" one particular value, and/or to "about"
another particular value. When such a range is expressed, another
embodiment includes from the one particular value and/or to the
other particular value. Similarly, when values are expressed as
approximations, by use of the antecedent "about," it will be
understood that the particular value forms another embodiment. It
will be further understood that the endpoints of each of the ranges
are significant both in relation to the other endpoint, and
independently of the other endpoint.
[0029] "Optional" or "optionally" means that the subsequently
described event or circumstance may or may not occur, and that the
description includes instances where said event or circumstance
occurs and instances where it does not.
[0030] Throughout the description and claims of this specification,
the word "comprise" and variations of the word, such as
"comprising" and "comprises," means "including but not limited to,"
and is not intended to exclude, for example, other additives,
components, integers or steps. "Exemplary" means "an example of and
is not intended to convey an indication of a preferred or ideal
embodiment. "Such as" is not used in a restrictive sense, but for
explanatory purposes.
[0031] As used herein, the term "polybasic" refers to a molecule
having more than one acidic proton.
[0032] As used herein, the term "Lewis basic atom" refers to an
atom having at least one lone pair of electrons capable of
coordinating to a proton or metal ion.
[0033] As used herein, the term "tritopic ligand" refers to a
compound having a central core, wherein three arms extend from the
core, each arm being terminated by a functional group or chemical
moiety having at least one Lewis basic atom.
[0034] As used herein, the term "tridentate group" refers to a
chemical moiety having three Lewis basic atoms arranged such that
all three Lewis basic atoms can be coordinated to the same metal
ion at the same time.
[0035] As used herein, the term "sol-gel transition temperature"
refers to the temperature point at which a material/solvent mixture
changes between a colloidal solution and an integrated network.
[0036] Disclosed are components that can be used to perform the
disclosed methods and systems. These and other components are
disclosed herein, and it is understood that when combinations,
subsets, interactions, groups, etc. of these components are
disclosed that while specific reference of each various individual
and collective combinations and permutation of these may not be
explicitly disclosed, each is specifically contemplated and
described herein, for all methods and systems. This applies to all
aspects of this application including, but not limited to, steps in
disclosed methods. Thus, if there are a variety of additional steps
that can be performed it is understood that each of these
additional steps can be performed with any specific embodiment or
combination of embodiments of the disclosed methods.
[0037] Self-Healing Conductive Networks
[0038] Disclosed herein are self-healing, conductive networks. The
networks can be gels at room temperature, and contain at least one
conducting polymer, at least one supramolecular complex, and at
least one solvent. In other embodiments, the networks can be liquid
at room temperature, and only form gels at lower temperature.
[0039] The networks can be characterized by a conductivity of at
least 5 S/m, at least 10 S/m, at least 15 S/m, at least 20 S/m, at
least 25 S/m, at least 30 S/m, at least 35 S/m, at least 40 S/m, at
least 45 S/m, or at least 50 S/m.
[0040] The networks can be characterized of a dynamic storage
modulus (G') of at least 10 KPa, at least 15 KPa, or at least 20
KPa, as measured using rheological experiments performed by a
rheometer in a frequency sweep mode.
[0041] The networks can be characterized of a loss modulus (G'') of
at least 1 KPa, at least 1.5 KPa, or at least 2.0 KPa, as measured
using rheological experiments performed by a rheometer in a
frequency sweep mode.
[0042] In some embodiments, after the network has undergone a
breaking followed by self-healing, the conductivity of the
self-healing network will be at least 50%, 60%, 70%, 80%, 90%, 95%,
97.5% or 99% of the conductivity of the network prior to
breaking.
[0043] In some embodiments, after the network has undergone a
breaking followed by self-healing, the dynamic storage modulus of
the self-healing network will be at least 50%, 60%, 70%, 80%, 90%,
95%, 97.5% or 99% of the dynamic storage modulus of the network
prior to breaking.
[0044] In some embodiments, after the network has undergone a
breaking followed by self-healing, the loss modulus of the
self-healing network will be at least 50%, 60%, 70%, 80%, 90%, 95%,
97.5% or 99% of the loss modulus of the network prior to
breaking.
[0045] In some embodiments, after the network has undergone a
breaking followed by self-healing, the conductivity of the
self-healing network will be at least 80%, of the conductivity of
the network prior to breaking, the dynamic storage modulus of the
self-healing network will be at least 80% of the dynamic storage
modulus of the network prior to breaking, and the loss modulus of
the self-healing network will be at least 80% of the loss modulus
of the network prior to breaking.
[0046] The networks can contain one or more conductive polymers and
one or more supramolecular complexes. The supramolecular complex
can be introduced into conductive polymer matrix, resulting in a
network of the two components. In this network, the nanostructured
conductive polymer gel constructs a 3D network to promote the
transport of electrons and mechanically reinforce the network while
the supramolecular complex contributes to self-healing property and
also conductivity.
[0047] Conductive Polymers
[0048] The conductive polymer can include a polyaniline, a
polypyrrole, a polyfuran, a polythiophene,], which may either be
unsubstituted or substituted with one or more functional groups. In
certain embodiments, the conductive polymer may include a compound
having either of the following formulae:
##STR00001##
wherein R is C.sub.1-6 alkyl,C.sub.1-6 alkoxy, C.sub.1-6
haloalkyl,C.sub.1-6 haloalkoxy, F, Cl, Br, I, CN, NO.sub.2, n is 0,
1, 2, 3 or 4, and m is 0, 1 or 2. Compounds in which X is NH are
designated polypyrroles, when X is O are designated polyfuran, when
X is S are designated polythiophene, and when X is Se are
designated polyseleophene. In some embodiments, the conductive
polymer can include compounds in which X is a mixture of O, S
and/or NH. For instance, the conductive polymer can be a polyfuran
wherein 1-5% of the X groups are N or S. In some embodiments it is
preferred than n and m are both 0.
[0049] The conductive polymer can include one or more dopants.
Exemplary dopants include polybasic compounds. In some embodiments,
the dopant can have at least two, at least three, at least four, at
least five, or at least six acidic groups. Exemplary acidic groups
include carboxylic acids, sulfonic acids, and phosphoric acids. In
some embodiments, the dopant can include one or polyacids, for
instance, polystyrene sulfonic acid (PSS),
poly(3,4-ethylenedioxythiophene) polystyrene sulfonic acid,
poly(vinylphosphoric acid) or poly(meth)acrylic acid (including
both methacrylic and acrylic acids), and salts of the same (e.g.,
Li, Na, K, Mg, Ca, and ammonium salts, including ammonia and
substituted amines). Preferred dopants include aromatic rings
substituted with 3 or more carboxylic acids, e.g., 1,2,4,5
benzenetetracarboxylic acid. Other dopants include copper
phthalocyanine-3,4',4'',4'''-tetrasulfonic acid tetrasodium salt
(CuPcTs) and phytic acid, phytic acid being particularly
preferred.
[0050] Conductive polymers can be obtained using an oxidative
polymerization protocol. Generally, the monomer and dopant can be
combined in a first solvent, and an oxidant is combined with a
second solvent. Exemplary monomers include aniline, pyrrole,
thiophene, toluidine, anisidine and other derivatives of aniline
such as methylaniline, ethyl aniline, 2-alkoxyaniline, and
2,5-dialkoxyaniline. Exemplary oxidants include persulfates such as
(NH.sub.4).sub.2S.sub.2O.sub.8, Na.sub.2S.sub.2O.sub.8 and
K.sub.2S.sub.2O.sub.8, metal salts such as iron (III) chloride,
copper (II) chloride, silver nitrate, chloroauric acid and ammonium
cerium(IV) nitrate, and peroxides such as hydrogen peroxide. The
solvent can be water, an organic solvent, or a mixture thereof. In
solvent mixtures of organic solvents and water, the organic solvent
can be water miscible or water immiscible. Exemplary water
immiscible solvents include haloalkanes such as methylene chloride
carbon tetrachloride, chloroform, and dichloroethane, hydrocarbons
such as benzene, toluene, xylene, and hexane. In some cases the
solvent can be an ethers such as diethylether, or the solvent can
be carbon disulfide. In certain embodiments, the oxidant is
combined with water, while the monomer/dopant is combined in a
water miscible organic solvent. Exemplary water miscible organic
solvents include alcohols such as methanol, ethanol, isopropanol,
glycerol, and ethylene glycol, ethers such as THF, 1,4-dioxane,
dimethoxy ethane, and other solvents such as acetone, acetonitrile,
DMSO, and DMF.
[0051] The oxidant can be added to the monomer/dopant/solvent
mixture, either neat or dissolved in a solvent. Sonication or other
forms of mixing may be employed to ensure complete dissolution in
the solvent prior to or after combining. In certain embodiments the
mixture can be in a mold to control the eventual shape of the
conductive polymer. After the polymerization is complete, the
resulting polymer can be purified by conventional processes such as
dialysis or washing with deionized or distilled water.
[0052] Conductive polymers prepared according to the above method
can be obtained as hydrogels when water is present as a solvent.
Conductive polymer hydrogels can be converted to aerogels by
dehydrating the hydrogel using techniques such as lyophilization.
In some embodiments, the aerogel can be characterized by a water
content of less than about 5%, less than about 4%, less than about
3%, less than about 2%, less than about 1%, or less than about
0.5%by weight, as measured by KF.
[0053] Supramolecular Complexes
[0054] The supramolecular complex can be an organometallic complex,
and in certain embodiments the supramolecular complex can have a
cubic architecture. The supramolecular complex, when apart from the
conductive polymer, can be formulated as a composition
characterized by a sol-gel transition of less than or about
80.degree. C., less than or about 70.degree. C., less than or about
60.degree. C., or less than or about 50.degree. C. Preferably the
sol-gel transition is less than about 60.degree. C. Cubic
supramolecular organometallic complexes can include tritopic
ligands, held together by ditopic metal-ligand bonds. The tritopic
ligands form the vertices of the cube, which are held together by
the ditopic metal-ligand bond. Such a cube can be represented by
the molecular formula:
M.sub.12L.sub.8,
wherein M is a metal atom, and L is a tritropic ligand. In some
embodiments, the metal ion can be a transition metal such as Zn,
Cd, Ni, Co, Fe, Ru, and Mn. In certain preferred embodiments, the
transition metal is Zn.
[0055] The tritopic ligand can be represented by the Formula I:
##STR00002##
wherein: [0056] Z is a group of the formula:
##STR00003##
[0056] wherein each represents a bond to a B.sup.3.sub.yyy
B.sup.3.sub.yyy group, .PHI. represents a 1,4 phenylene, z is
either 0 or 1, and R.sup.z is selected from hydrogen, C.sub.1-12
alkyl, C.sub.1-12 cycloalkyl, C.sub.2-12 alkoxy, C.sub.2-12
heterocyclyl, C.sub.6-12 aryl, C.sub.3-12 heteroaryl, poly(alkylene
glycol), crown ethers (e.g., 12-4, 15-5, 18-6, 18-6 and the like),
and pillarenes (macrocycles having multiple 1,4 hydroquinone units
arranged in the ring); [0057] x, xx, and xxx are each independently
0 or 1, and A.sup.1, A.sup.2 and A.sup.3 are independently selected
from:
##STR00004##
[0057] y, yy, and yyy are each independently 0, 1 or 2, and
B.sup.1, B.sup.2 and B.sup.3 are independently selected from
##STR00005##
wherein R is in each case independently selected from hydrogen,
halogen (e.g., F, Cl, Br, I), OH, COOH, NO.sub.2, C.sub.1-6 alkyl,
C.sub.1-6 haloalkyl, C.sub.3-6 cycloalkyl, C.sub.1-6 alkoxy,
C.sub.2-12 heterocyclyl, C.sub.6-12 aryl, C.sub.3-12 heteroaryl,
and wherein any two or more R groups may together form a ring;
[0058] with the proviso that the sum of x, xx, xxx, y, yy, and yyy
is not 0; [0059] R.sup.b and R.sup.d are independently selected
hydrogen, halogen (e.g., F, Cl, Br, I), OH, COOH, NO.sub.2,
C.sub.1-6 alkyl, C.sub.1-6 haloalkyl, C.sub.3-6 cycloalkyl,
C.sub.1-6 alkoxy, C.sub.2-12 heterocyclyl, C.sub.6-12 aryl,
C.sub.3-12 heteroaryl; [0060] R.sup.b and R.sup.d are independently
selected from:
##STR00006##
[0061] or wherein either R.sup.a and R.sup.b or R.sup.c and
R.sup.d, together form a group having the structure:
##STR00007##
wherein R.sup.1 is in each case independently selected from
hydrogen, halogen, C.sub.1-C.sub.6 alkyl, C.sub.1-C.sub.6 alkoxy,
C.sub.1-C.sub.6 haloalkyl, R.sup.2 is in each case independently
selected from C.sub.1-C.sub.6 alkyl, and wherein any two or more of
R.sup.1 or R.sup.2 may together form a ring. [0062] In certain
embodiments, R.sup.a and R.sup.c are each:
##STR00008##
[0062] wherein R.sup.1 is either hydrogen or C.sub.1-6 akyl such as
methyl or t-butyl. Selection of such 4-substitued pyridin-2-yl
groups for R.sup.a and R.sup.c provides a tritopic ligand having
the Formula Ia:
##STR00009## [0063] wherein Z, x, xx, xxx, A.sup.1, A.sup.2 and
A.sup.3, y, yy, yyy, B.sup.1, B.sup.2, B.sup.3, R.sup.b and R.sup.d
are as defined above, and R.sup.1 is either hydrogen or C.sub.1-6
alkyl. In some embodiments of either Formula I or Ia, R.sup.b and
R.sup.d are each hydrogen.
[0064] In certain embodiments, Z is a group having the formula:
##STR00010##
wherein R.sup.z, z and .PHI. are as defined above.
[0065] In certain embodiments, each of A.sup.1, A.sup.2 and
A.sup.3, if present, are acetylenyl, e.g.:
##STR00011##
[0066] In some embodiments, each of wherein B.sup.1, B.sup.2 and
B.sup.3, if present, are each:
##STR00012##
wherein R is as defined above. In certain embodiments, each R is
hydrogen. [0067] In certain embodiments, x, xx, xxx, y, yy, and yyy
may each be selected to give the following tritopic ligands:
##STR00013##
[0067] wherein R.sup.a, R.sup.b, R.sup.c, R.sup.d and Z are as
defined above, and R is independently selected from hydrogen,
halogen (e.g., F, Cl, Br, I), OH, COOH, NO.sub.2,C.sub.1-6 alkyl,
C.sub.1-12 haloalkyl, C.sub.3-6 cycloalkyl, C.sub.1-6 alkoxy,
C.sub.2-12 heterocyclyl, C.sub.6-12 aryl, C.sub.3-12 heteroaryl,
and wherein any two or more R groups may together form a ring.
Methods of Making Tritopic Ligands
[0068] The tritopic ligands can be assembled using conventional
heterocyclic and organometallic protocols. Tri-and
tetra-4-halophenyl methyl and silyl compounds are commercially
available and can also be prepared by conventional methods.
4-halophenyl adamantyl derivatives can be prepared according to the
following sequences:
##STR00014## ##STR00015##
[0069] In some embodiments, individual A and B units can be joined
using Suzuki, Heck, Hiyama, Kumada, Negishi, Stille, and
Sonogashira chemistries. By way of examples, the following
sequences can be used to prepare certain embodiments:
##STR00016##
[0070] Variations and combinations of the above reactions can be
used to prepare other
A.sup.1.sub.xB.sup.1.sub.yA.sup.2.sub.xxB.sup.2.sub.yyA.sup.3.sub.xxxB.su-
p.3.sub.yyy systems. The specific reaction conditions
(catalyst/ligand system, time, temperature, and solvent) can be
determined by those have ordinary skill in the art. Other methods
of preparing aryl-aryl and aryl-alkynyl groups are known and can be
employed as needed by those of skill in the art.
[0071] In some embodiments, symmetrically substituted pyridines
(i.e., those in which R.sup.a is the same as R.sup.c, and R.sup.b
is the same as R.sup.d) can be obtained via the following
reaction:
##STR00017##
[0072] Asymmetrically substituted pyridines can be obtained
according to the following reaction:
##STR00018##
[0073] In the above sequences, R.sup.a, R.sup.b, R.sup.c, and
R.sup.d as defined above. Q can be substituted phenyl, alkynyl,
halogen, hydroxyl and protected hydroxyl (i.e., silyl ethers,
esters, benzyl ethers and the like), --boronic acid or boronic
esters. Hydroxyl groups can subsequently be converted to
cross-coupling reactive groups such as triflate, mesylate,
phosphonate or sulfonate. The specific reaction conditions (time,
temperature, solvent, nitrogen source) can be determined by those
have ordinary skill in the art. Other methods of pyridine synthesis
are known and can be employed as necessary.
Methods of Making Supramolecular Complexes
[0074] The supramolecular complexes can be formed by combining a
metal salt and tritopic ligand together in an appropriate
stoichiometric ratio. For instance, complexes having the Formula
M.sub.12L.sub.8 are assembled using 1.5 molar equivalents of metal
to tritopic ligand. Suitable metal sources include salts such as
nitrate salts (e.g., Zn(NO.sub.3).sub.2), halide salts (e.g.,
CdCl.sub.2), and other salt forms known to those of skill in the
art. The metal salt and tritopic ligand can be combined in a
solvent, and then heated for a time sufficient assemble the
supramolecular complex, followed by a precipitation step to isolate
the complex. In some embodiments, the precipitation step includes a
counterion exchange step to adjust the solubility of the complex.
Exemplary counterions which may be used include nitrates,
triflates, and non-coordinating anions such as tetrafluoroborate,
hexafluorophosphate, tetrakis(pentafluorophenyl)borate, or bi
s(trifluoromethyl sulphonyl)imidate.
Methods of Making Networks
[0075] In certain embodiments, the network can be obtained by
combining an aerogel and supramolecular complex together in a
solvent, followed by partial evaporation of the solvent. The ratio
of aerogel to supramolecular complex (w/w) can be from about 25:1
to 1:25, from about 25:1 to 1:10, from about 20:1 to 1:10, from
about 20:1 to 1:5, from about 20:1 to 1:1, from about 15:1 to 1:1,
or from about 10:1 to 1:1. The network, after partial evaporation,
can contain solvent in an amount about 25-75%, about 30-70%, about
35-65%, about 40-60%, or about 45-55%. Suitable solvents include
organic solvents, such as polar aprotic solvents. Exemplary polar
aprotic solvents which can be used in the network include
acetonitrile, THF, DMF and DMSO
EXAMPLES
[0076] The following examples are set forth below to illustrate the
methods and results according to the disclosed subject matter.
These examples are not intended to be inclusive of all aspects of
the subject matter disclosed herein, but rather to illustrate
representative methods, compositions, and results. These examples
are not intended to exclude equivalents and variations of the
present invention, which are apparent to one skilled in the
art.
[0077] Efforts have been made to ensure accuracy with respect to
numbers (e.g., amounts, temperature, etc.) but some errors and
deviations should be accounted for. Unless indicated otherwise,
parts are parts by weight, temperature is in .degree. C. or is at
ambient temperature, and pressure is at or near atmospheric. There
are numerous variations and combinations of reaction conditions,
e.g., component concentrations, temperatures, pressures, and other
reaction ranges and conditions that can be used to optimize the
product purity and yield obtained from the described process. Only
reasonable and routine experimentation will be required to optimize
such process conditions.
[0078] All reagents were purchased from Aldrich, Matrix Scientific,
Alfa Aesar and used without further purification.
((trimethylsilyl)ethynyl)benzaldehyde, 3
1-(4-tert-butylpyridin-2-yl)ethanone4 and
1,3,5,-tri(4-iodophenyl)-adamantane were synthesized according to
the reported methods. Column chromatography was conducted using
basic Al2O.sub.3 (Brockman I, activity, 58 .ANG.) or SiO.sub.2
(VWR, 40-60 um, 60.ANG.) and the separated products were visualized
by UV light. .sup.1H NMR and .sup.13C NMR spectra data were
recorded on a Bruker Avance 400-MHz and 600-MHz NMR spectrometer in
CDCl3 and CD3CN with TMS standard. UV--vis absorption (UV) spectra
were recorded with a Varian Cary 100 UV/Vis Spectrometer.
Photoluminescence (PL) spectra were obtained on a PerkinElmer LS50B
Luminescence spectrometer. Electrospray ionization (ESI) mass
spectra were recorded with a Waters Synapt G2 tandem mass
spectrometer, using solutions of 0.01mg sample in 1 mL of
CHCl.sub.3/CH.sub.3OH (1:3, v/v) for ligand or 0.5 mg in 1 mL of
MeCN/MeOH (3:1, v/v) for complex.
Example 1
Synthesis of Supramolecular Complex
[0079] To a solution of NaOH powder (1.6 g, 40 mmol) in 25 ml EtOH,
4-((trimethylsilyl)ethynyl)benzaldehyde (1.0 g, 5.0 mmol) and
4-tert-Butyl-2-acetylpyridine (2.0 g, 11.3 mmol) was added. After
stirring at 25.degree. C. for 6 h, aqueous NH.sub.3.H.sub.2O (20
mL) was added and the mixture was refluxed for 20 h. After cooling
to room temperature, the precipitate was filtered and washed with
cold ethanol to give 1 as white solid: 1.2 g (54%); .sup.1H NMR
(400 MHz, CDCl3): .delta. 8.82 (dd, J=2.1, 0.8 Hz, 2H, tpy-H
3,3''), 8.74 (s, 2H, tpy-H 3', 5'), 8.66 (dd, J=5.2, 0.7 Hz, 2H,
tpy-H 6,6''), 7.95 -7.86 (m, 2H, Ph-H B), 7.69 -7.61 (m, 2H, Ph-H
A),7.39 (dd, J=5.2, 2.0 Hz, 2H, tpy-H 5,5''), 3.20 (s,1H), 1.47 (s,
18H). .sup.13C NMR (100 MHz, CDCl3): .delta. 160.79, 156.13,
155.97, 149.32, 149.08, 138.94, 132.64, 127.27, 122.72, 121.16,
118.47, 118.25, 83.36, 78.44, 34.96, 30.54. ESI-HRMS (m/z): Calcd.
For [C.sub.31H.sub.31N.sub.3+H].sup.+: 446.2596. Found:
446.2595.
[0080] To a flask containing Pd(PPh.sub.3).sub.2Cl.sub.2 (56 mg,
0.08 mmol), CuI (7.6 mg, 0.04 mmol) and
1,3,5,-tri(4-iodophenyl)-adamantane (4) (370 mg, 0.5 mmol) in 20 ml
THF, 8 ml Et.sub.3N was added. After stirring at room temperature
for 10 minutes, the solution of the compound 1 (756 mg, 1.7 mmol)
in 10 ml THF was slowly added over 1 h. The mixture was heated at
40.degree. C. for 2 days. After removal of the volatile, the
residue was purified by column chromatography on Al.sub.2O.sub.3
with chloroform as eluent to afford LA in 66% yield as a yellow
solid. .sup.1H NMR (400 MHz, CDCl.sub.3): .delta. 8.83 (s, J=2.0,
0.8 Hz, 6H, tpy-H 3,3''), 8.77 (s, 6H, tpy-H 3',5'), 8.67 (d, J
=5.2, 0.7 Hz, 6H, tpy-H 6,6''), 7.97-7.91 (m, 6H, Ph-H D), 7.72
-7.68 (m, 6H, Ph-H C), 7.59 (d, J=8.6 Hz, 6H, Ph-H B), 7.49 (d,
J=8.8 Hz, 6H, Ph-H A), 7.39 (dd, J=5.3, 2.0 Hz, 6H, tpy-H 5,5''),
2.62 (m, 1H), 2.17 (s, 6H), 2.07 (s, 6H), 1.48 (s, 54H). .sup.13C
NMR (100 MHz, CDCl3): .delta. 160.79, 156.09, 156.04, 150.15,
149.45, 149.08, 138.12, 132.10, 131.70, 127.27, 125.11, 124.14,
121.13, 120.81, 118.41, 118.26, 90.87, 88.89, 47.70, 41.21, 38.48,
34.99, 30.54, 30.06. ESI-HRMS (m/z): Calcd. for
[C.sub.121H.sub.115N.sub.9+2H].sup.2- and
[C.sub.121H.sub.115N9+3H].sup.3+: 847.9716 and 565.6530. Found:
847.9710 and 565.6525.
[0081] To a solution of ligand LA (6.5 mg, 3.8 .mu.mol) in
CHCl.sub.3 (1 mL), a solution of Zn(NO.sub.3).sub.2.6H.sub.2O (1.7
mg, 5.7 .mu.mol) in MeOH (3 mL) was added; then the mixture was
stirred at 50.degree. C. for 8 h. After cooling to room
temperature, 200 mg NH.sub.4PF.sub.6 was added to give a white
precipitate, and used water to wash and obtained product (yield:
93%). 1H NMR (400 MHz, CD3CN): .delta. 9.09 (s, 6H, tpy-H 3',5'),
8.69 (s, 6H, tpy-H 3,3''), 8.33 (s, 6H, Ph-H D), 7.95 (s, 6H, Ph-H
C), 7.72 (m, 18H, tpy-H 6,6'', Ph-H B , and Ph-H A), 7.44 (s, 6H,
tpy-H 5,5''), 1.41 (s, 54H). 13C NMR (150 MHz, CD.sub.3CN): .delta.
166.41, 154.85, 151.03, 149.71, 147.13, 135.58, 131.91, 131.20,
128.05, 125.15, 123.98, 120.97, 38.25, 35.15, 29.39. ESI MS (m/z):
1635.8 [M-9PF6.sup.-].sup.9+ (calcd m/z:1635.8), 1637.7
[M-10PF6.sup.-].sup.10+ (calcd m/z: 1637.7), 1475.7
[M-11PF6.sup.-].sup.11+ (calcd m/z: 1475.7), 1340.6
[M-12PF6.sup.-].sup.12+ (calcd m/z: 1340.6), 1226.3
[M-13PF6.sup.-].sup.13+ (calcd m/z: 1226.3), 1128.3
[M-14PF6.sup.-].sup.14+ (calcd m/z: 1128.3), 1043.5 [M-15PF6.sup.-
(calcd m/z: 1043.5), 969.2 [M- 16PF6.sup.-].sup.16+ (calcd m/z:
969.2), 903.6 [M-17PF6.sup.-].sup.17+ (calcd m/z:903.6), 845.4
[M-18PF6.sup.-].sup.18+ (calcd m/z: 845.4), 793.2
[M-19PF.sub.6.sup.-].sup.19+ (calcd m/z: 793.2), 746.4
[M-20PF.sub.6].sup.20+ (calcd m/z: 746.4), 703.9
[M-21PF.sub.6.sup.-].sup.21+ (calcd m/z: 703.9), 665.3
[M-22PF.sub.6].sup.22 + (calcd m/z: 665.3), and 630.0
[M-23PF.sub.6.sup.-].sup.23+ (calcd m/z: 630.0).
Example 2
Preparation of Network
[0082] In a typical synthesis process, solution A was prepared by
dissolving pyrrole (84 .mu.L) and phytic acid solution (50 wt %,
184 .mu.L) in isopropanol (1 mL), followed by ultrasonicating for 5
mins. Then solution B was prepared by dissolving ammonium
persulfate (APS) (184 mg) acting as initiator in deioned water (DI,
1 mL). The PPy hydrogel was polymerized by mixing solution A and B
together. The as-prepared PPy hydrogel was immersed in DI for
purification overnight and free-dried to obtain the PPy aerogel.
Then the supramolecular complex of Example 1 (5 mg) was dissolved
in acetonitrile (1 mL) and heated above 50.degree. C. until a clear
solution formed. The supramolecule solution was dipped into the PPy
aerogel and the hybrid gel could form when temperature
decreased.
[0083] Example 3
Preparation of Network Thin Film
[0084] Solution A and B were prepared as described above and dipped
onto flexible substrates to form PPy hydrogel film. The PPy
hydrogel film was then purified and freeze dried to obtain PPy
aerogel film. Then the supramolecule gel was introduced into the
aerogel film and network film could be obtained.
[0085] The compositions and methods of the appended claims are not
limited in scope by the specific compositions and methods described
herein, which are intended as illustrations of a few aspects of the
claims and any compositions and methods that are functionally
equivalent are intended to fall within the scope of the claims.
Various modifications of the compositions and methods in addition
to those shown and described herein are intended to fall within the
scope of the appended claims. Further, while only certain
representative compositions and method steps disclosed herein are
specifically described, other combinations of the compositions and
method steps also are intended to fall within the scope of the
appended claims, even if not specifically recited. Thus, a
combination of steps, elements, components, or constituents may be
explicitly mentioned herein or less, however, other combinations of
steps, elements, components, and constituents are included, even
though not explicitly stated. The term "comprising" and variations
thereof as used herein is used synonymously with the term
"including" and variations thereof and are open, non-limiting
terms. Although the terms "comprising" and "including" have been
used herein to describe various embodiments, the terms "consisting
essentially of" and "consisting of" can be used in place of
"comprising" and "including" to provide for more specific
embodiments of the invention and are also disclosed. Other than in
the examples, or where otherwise noted, all numbers expressing
quantities of ingredients, reaction conditions, and so forth used
in the specification and claims are to be understood at the very
least, and not as an attempt to limit the application of the
doctrine of equivalents to the scope of the claims, to be construed
in light of the number of significant digits and ordinary rounding
approaches.
* * * * *